Masked mastoiditis

Masked mastoiditis
Classification and external resources
ICD-10	H70.09
ICD-9-CM	383.9

Masked mastoditis is a condition of slow destruction of mastoid air cells but without the acute signs and symptoms often seen in acute mastoiditis. There is no pain, no discharge, no fever and no mastoid swelling but mastoidectomy may show extensive destruction of the air cells with granulation tissue and dark gelatinous material filling the mastoid. It is not surprising to find erosion of the tegmen tympani and sinus plate with an extradural or perisinus abscess. Its occur commonly in infants and characterized by the symptom of a gastrointestinal intoxication and otitis media.^[1]

Aetiology

The condition often results from inadequate antibiotic therapy in term of dose, frequency and duration of administration . Most often it results from use of oral penicillin given in cases of acute otitis media when acute symptoms subside but smouldering infection continues in the mastoid. No evidence of bacterial viral parasitical pathogen cause effect an masked mastoiditis.

Clinical features

Patient is often a child, not entirely feeling well, with mild pain behind the ear but with persistent hearing loss. Tympanic membrane appears thick with loss of translucency Slight tenderness may be elicited over the mastoid. Audiometry shows conductive hearing loss of variable degree. X-ray of mastoid will reveal clouding of air cells with loss of cell outline.

Diagnosis

Many cases are referred to hospital because of the persistence of pain, deafness, fever and discharge or because of the appearance of an intact unresolved reddish drumhead. Others are seen on account of recurrence of these symptoms after an apparent recovery. The persistence of deafness is an important symptom. There may be mastoid tenderness and headache with a slight rise in temperature. The drumhead usually congested and full or thickened in appearance. Mastoid radiographs show opacity haziness in some cases and cellular outlines on the affected side .

Children frequently present with severe otalgia with pain and tenderness behind the ear. However, only are such cases due to acute mastoiditis. The conditions that are most often misdiagnosed as acute mastoiditis are acute suppurative otitis of externa, meatal furunculosis and suppuration of postauricular lymph nodes. The differentiation of these conditions from mastoiditis, although sometimes difficult, can usually be made on clinical grounds. The features strongly suggestive masked mastoiditis are a recent history of acute media, deafness, discharge and an abnormal tympanic membrane with sagging of the posterosuperior meatal wall. Difficulty can arise in cases of acute otitis externa and furunculosis with secondary postauricular lymphadenitis, particularly when canal oedema prevents a view of the tympanic membrane. In these latter conditions acute pain is often exacerbated by traction of the pinna, and there may be tenderness over the tragus. In these difficult cases the diagnosis of masked mastoiditis can be confirmed or ruled out by the appearance of opaque mastoid air cells on CT cell.^[2]

Treatment

Admission to hospital for observation and adequate treatment is necessary. Resumption of full antibiotic therapy is justifiable in the absence of acute signs of mastoiditis, a watch being kept on the patient's general condition, temperature chart, tympanic membrane, mastoid process and hearing. In the absence of early signs of improvement, and whenever some doubt exists, a cortical absence of mastoidectomy should be done to provide effective drainage of the middle ear and reduce the possibility of permanent conductive deafness.

The Cortical Mastoid Operation (Schwartze's operation). The operation is done to remove all infected mastoid cells. A postural incision is made, the mastoid bone is exposed and MacEwen’s triangle identified. The cortex is removed using a drill, although where an abscess is the cortex will be soft and necrotic. Each group of cells is systematically explored and cleared leave an appearance. Particular attention is paid to so as to removing infection in the tip cells and the cell in the sinodural angle. If necessary the zygomatic cells are removed. If the plates of bone overlying the dura mater and the lateral sinus appear healthy they are not opened to exposed these structure, but unhealthy bone n these situation must be removed and the dura and sinus wall examined for extension of disease.^[3]

References

1. PL Dhingra, Shruti Dhingra. "12". Disese of EAR, NOSE and THROAT & HEAD and NECK SURGERY (6 ed.). ELSEVIER. p. 79. ISBN 9788131234310.
2. Harold Ludman, Tony Wright. Disease of the EAR (6 ed.). JAYPEE Brothers. p. 410. ISBN 8180619338.
3. Logan Turner. Maran, AGD, ed. LOGAN TURNER'S DISEASES of the Nose, Throat and Ear (10 ed.). JAYPEE Brothers. p. 299. ISBN 0750616431.